The aim of this study was to identify the potential antibacterial effects of gatifloxacin on periodontal pathogens including Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, and Prevotella intermedia. The minimum inhibitory concentrations (MIC) of gatifloxacin and its bactericidal effects were investigated. Gatifloxacin inhibited the growth of all three kinds of periodontopathic bacteria tested in broth. The MIC value of 2.5 nM was found to be the most effective in inhibiting A. actinomycetemcomitans. An adenosine triphosphate bioluminescence assay revealed that gatifloxacin exhibited bactericidal effects on the tested bacteria in a time-dependent manner. The safety of gatifloxacin in mammalian cells was evaluated by assessing the viability of normal human dermal fibroblast (NHDF) cells treated with gatifloxacin. Almost all NHDF cells survived after 2-d culture, while 81% of the cells survived after 4-d culture when treated with 1.0 × 10 3 nM gatifloxacin. These results indicate that gatifloxacin is a possible drug for local administration to prevent periodontal infection.

The aim of this study was to investigate properties of atelocollagen/gelatin complexes (AC/Gel) and their characteristics of sustained statin release, to assess the utility of AC/Gel. AC/Gel were prepared by changing the mixing ratio of AC (0 to 40% of AC). Analysis of spectra of fluvastatin (Flu), gelatin (Gel), and Flu with Gel complex using a Fourier transform-infrared spectrometer indicates that Flu was bound to Gel through a bond involving the carboxyl and amino groups. Evaluation of characteristics of sustained release of Flu from the AC/Gel using an ultraviolet-visible spectrophotometer showed that the release rate of Flu decreased with increasing the AC content. The histological evaluation using of Sprague-Dawley rats suggest that, unlike the pure Gel sponge, the AC/Gel was not absorbed in an early stage. Therefore, the present study showed that sustained Flu release can be controlled by using an AC/Gel, suggesting the utility of this composite material.